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      内容区域<br>
      <button onclick="changeTheme('zhongqiu')">中秋</button>
      <button onclick="changeTheme('yuandan')">元旦</button>
      <button onclick="changeTheme('chunjie')">春节</button>
      <button onclick="changeTheme('caodi')">草地</button>
      <button onclick="changeTheme('christmas')">圣诞</button>
      <button onclick="changeTheme('yueyechuanshuo')">月夜传说</button>
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      document.querySelector('#link').href = `./${type}.css`
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